Process of making metallic cyanids.



N0 MODEL.

PATENTBD NOV. 29, 1904. M. VOIGT & A. R. FRANK. PROCESS 0F MAKINGMETALLIC GYANIDS. l

APPLICATION FILED DEG. 23, 1902.

Miren STATES Patented November 29, e.

Parenti" (ferrer.

MAX VOIGT, OF GHARLOTTENBURG, AND ALBERT lt. FRANK, VOF BERLIN, GERMANY,ASSIGNORS TO THE FIRM CYANIDGESELLSCHAFT MIT BESCHRAENKTER HAFTIUNG, OFBERLlN, GERMANY.

PRCESS OF MAKING METALhlC (DYANIS.

SPECIFICATION forming part of Letters-Patent N0. 775,953, dated November29, 1904.

Application filed December 23, 1902. Serial No. 136,412. (No specimens.)

Be it known that we, MAX Vore'r, residing at 28 Teltowerstrasse, Berlin,and ALBERT R. FRANK, residing at 26 Berlinerstrasse, Charlottenburg,Kingdom of lfrussia, German Empire, subjects of the KingofPrussia,Emperor of Germany, have invented new and useful .Improvements inProcesses of Manufacturing Metal Cyanids, of which the following is aspecification.

This invention relates to a process for obtainingV metallic cyanids.

The process consists in the following steps: first, in treating'metallic cyanamids with water. From the solution thus obtained the freecyanamids are separated, then dried and heated up to the melting-pointin presence of metals, metallic oxids, or metallic salts, and thetemperature is maintained so high that the mixture remains liquid.

In the accompanying drawing an apparatus to be used for carrying out ourprocess is illustrated in vertical section.

a is a crucible; Z1, an exhaust; c, the cover of the Crucible; d, afurnace.

Already before this it has been proposed to convert metallic cyanamidsinto cyanids by heating metallic cyanamids together with carbon andmetallic compounds as fluxes up to melting-point. By this process,however, only impure metallic eyanids can be obtained, requiring afurther depuration. If, however, the metallic cyanamids are beforehandtreated with water or other suitable solvents and the thus obtained freecyanamids (which contain cyanamid and its polymers as dicyanamid,melamin, sometime-s mixed up together) melted in presence of metals,metallic oxids, metallic hydroxids, or metallic salts metallic cyanideof such a degree of purity are obtained that they can be used for mostindustrial purposes without requiring any further depuration. The aboveprocess is especially suitable for obtaining alkaline cyanids,especially cyanids of sodium and of potassium. As most suitable for theuse as metals or metallic com pounds have been found the easily-fusiblemetals and their easily-fusible oxids and saltas, for instance, metallicpotassium, sodium, hydroxid of potassium or of sodium, carbonate ofpotassium or of sodium, Snc. These can all be employed either singly ormixed up with each other. W e further have found that the amount ofmetallic cyanid obtained can be increased by adding carbonaceoussubstances to the mixture of cyanamid and metals or 1ne talliccompounds, either as carbon or as a compound of carbon-m5, for instance,as carbohydrogen. Either liquid, solid, or gaseous carbohydrogens can beused. So, for instance, coal-gas, mineral oils, paraffin, and vaselinehave been found suitable. The carbonaeious substance can be added beforeheating and the heating process then be proceeded with. However, thecarbonaceous substance can also be added while heating the mixture ofcyanamids with metals or metallic compounds by adding a carbohydrogen tothe heated mixture. So, for instance, coal-gas or another carbonaceousgas could be conducted into the mixture. The amount of carbonaceoussubstance is suitably so chosen that there is to each atom ofhydrogenized nitrogen one atom of carbon.

In the present process the nitrogen that is not bound as metallic oyanidgenerally escapes as ammonia or compounds of nitrogen. These can beconducted into a separate receptaele and be further utilized. It hasfurther been found advantageous to heat the cyanarnid with the metalliccompounds under pressure. The heating of the mixture can be done underpressure from the commencement, orthe heating can be commenced underordinary atmospheric pressure and the pressure be increased during theprocess of heating'. The skilled workman will lind the necessarytemperature and the respective quantities by experiment. The temperatureand the required `quantities are different for each metallic cyanid. lthas further been found advantageous to add such substances as willaccelerate the fusion. So,

for instance, any flux, as common salt, (sodium chlorid,) cyanid ofpotassium, cyanid of sodium, &c., can be added from the beginning orduring the process.

In the following the manner of obtaining cyanid of sodium is describedto illustrate the manner of carrying out the process. able metalliccyanamid-as, for instance, cyanamid of calcium or sodium or barium orleadis leached With water. Cyanamid of calcium is obtainedwfor instance,by conducting nitrogen into a mixture of lime and carbon, which isheated to about 2,000C centigrade. Cyanamid of bariums can be obtainedby letting ammoniac gas act on carbonate of barium. The metalliccyanamids are advantageously treated with Water, either boiling or cold.Ie may, however, separate the basis chemically, (by means of carbonicacid, sulfureted hydrogen, &c.) The solution is then separated from anyremaining sediment and brought to crystallization-for instance, bycooling the solution or evaporating same.

A skilled Workman will easily find the suitabler metallic cyanamid, thenecessary amount of Water or the chemical means for decomposing themetallic cyanamid, and the best manner of separating the cyanamid. rIhecyanamids are advantageously dried and mixed with metallic compounds-as,for instance, carbonate of sodium. A suitable mixture is as follows: onepart of Weight cyanamid, one part of Weight carbonate of sodium. Themixture is placed into a suitable vesselwfor instance, the crucible a,which is provided With an exhaust-tube and covered by the lid c. Thecrucible is placed into the furnace Z and heated. First, ammonia orcompounds of nitrogen Will escape by the exhaust b, then the Wholecontents Will melt, and the heating is continued so long until all isWell liquid. Then the process is completed. The cyanid obtained can bepoured out of the vessel when still liquid and can, if necessary, beseparated by filtration from such carbon as has remained intact.

The lreactions during this process are probably similar to thefollowing' equations:

First. In using metallic sodium:

NaOH-l- CNNHH- C I NaUN-l- NH3-i- CO (or b) 2NaoH+oNNH2+o=eNacNaLeHgo.Fourth. i/Vhen using carbonate of sodium:

A suit- Fifth. When usingcarbonate of sodium and f carbonaceoussubstances:

In the above equations the suffix a has been applied to signify that themolecular quantity of the substances employed is unknown. Exactly in thesame manner as the cyanamid its polymers Will react.

Instead of mixing' the substances and then heating them the process canbe carried out by bringing the cyanamid into the molten metallic alkalior alkalic compound, or a molten metallic alkali or alkalic compound canbe poured on a cyanamid equally melted beforehand. Also in this mannerof proceeding carbonaceous substances or fluxes separately or mixed witheach other may be added.

IVhat We claim as our invention, and desire to secure by Letters Patent,is-- l. A process for obtaining metallic cyanids which consists indissolving cyanamid from metallic cyanamids, separating the solution ofthe cyanamid, separating the cyanamid from the solution and heating theseparated cyanamid up to melting-point in presence of inorganicsubstances containing the base whose cyanid it is desired to produce.

2. A process for obtaining metallic cyanids which consists in dissolvingcyanamid from metallic cyanamids` separating the solution from thesediment formed in the dissolution of the cyanamid, separating thecyanamid from the solution and heating the separated cyanamid up tomelting-point in presence of easily-fusible compounds of metal Whosecyanid it is desired to produce.

3. A process for obtaining metallic cyanids Which consists in dissolvingcyanamid from metallic cyanamids, separating the solution from thesediment formed in the dissolution of the cyanamid, separating thecyanamid from the solution and heating the separated cyanamid up tomelting-point in presence of inorganic substances containing the baseWhose cyanid it is desired to produce and carbon.

4. A process for obtaining metallic cyanids which consists in dissolvingcyanamid from metallic cyanamids, separating the solution from thesediment formed in the dissolution from the solution and heating theseparated cyanamid up to melting-point in presence of inorganicsubstances containing the base whose cyanamid it is desired to produceand carbonaceous compounds. 5. A process for obtaining' metallic cyanidsWhich consists in dissolving cyanamid from metallic cyanamids,separating the solution from the sediment formed in the dissolution ofthe cyanamid, separating the cyanamid from the solution and heating theseparated cyanamid up to melting-point in' presence l l i l from thesediment, formed in the dissolution IoO IIO

IIS

of the cyanamid, separating the cyanamid oi" inorganic substancescontaining the base whose c vanid it is desired to produce, fluxpowdersand carbonaceous compounds.

6. A process for obtaining metallic cyanide which consists in dissolvingcyanamid from metallic cyanamids, separating the solution from thesediment formed in the dissolution oi' the cyanamid, separating thecyanarnid from the solution and heating the separated cyanamid up tomelting-point Linder pressure in presence of inorganic substancescontaining the base whose cyanid it is desired to produce.

7. A process for obtaining metallic cyanids Which consists indissolvingcyanamid from lmetallic cyanamids, separating the solutionfrom the sediment formed in the dissolution oi' the cyanamid, separatingthe cyanamid from the solution and heating' the separated cyanamid up tomelting-point under pressure in presence of inorganic substancescontaining the base Whose cyanid it is desired to produce andcarbonaceous compounds.

8. A process for obtaining metallic cyanide which consists in dissolvingcyanamid from metallic cyanamids, separating the solution from thesediment formed in the dissolution of the cyanamid, separating thecyanainid from the solution and heating the separated cyanamid up tomelting-point under pressure in presence of inorganic substancescontaining the base whose cyanid it is desired to produce, carbonaccouscompounds and iiuxpowders.

In Witness whereof We have hereunto signed our names, this 6th day ofDecember', 1902, in the presence of two subscribing witnesses.

MAX VOLGT. ALBERT R. FRANK. Witnesses:

HENRY HAsPER, WOLDEMAR HAUPT.

